Science: Deke's Comeback

It was a day that Donald K. ("Deke") Slayton would never forget. On
March 15, 1962, only two months before the taciturn astronaut was
scheduled to become the second American to orbit the earth, NASA
doctors abruptly grounded him. Reason: they had discovered an
occasional irregularity in the rhythm of his heartbeat. The bitterly
disappointed Slayton subsequently became chief of flight-crew
operations at the Manned Spacecraft Center and played a key role in
picking all future space crews, including the first men to land on the
moon. But even as he sent other...